Dispersing device

ABSTRACT

In a device for the dispersion of, in particular, low-viscosity to high-viscosity mixtures of substances, comprising a container having one or more openings for introducing the substances to be dispersed and one or more openings for discharging the dispersed substances, and at least one rotor and one stator, said at least one rotor being mounted for rotation relative to said stator about an axis of rotation, for the purpose of dispersing the substances that have been introduced into the container, fast and precisely metered introduction of substances at a controlled rate is achieved in that the stator is mounted for reciprocation in the direction of the rotation axis of the rotor and can be displaced by a displacement device within a specified range of movement and can be locked in an arbitrary position.

The invention relates to a device for the dispersion of, in particular,low-viscosity to high-viscosity mixtures of substances, comprising acontainer with one or more openings for introducing the substances to bedispersed and one or more openings for discharging the dispersedsubstances, and at least one rotor and one stator, said at least onerotor being rotatably mounted relative to said stator about an axis ofrotation for the purpose of dispersing the substances that have beenintroduced into the container.

Dispersing units of the type mentioned above are usually employed in theprior art for the purpose of mixing liquid substances with other liquidor powdered substances such that a substantially homogeneousdeagglomerated composition is formed. However, the prior dispersingunits all suffer from the drawback, in particular, that it is notreadily possible to carry out fast introduction of the substances.Furthermore, with the known dynamic devices, the input of energy intothe substances to be dispersed can only be controlled during adispersing operation by effecting a change of speed of a rotor. A changeof the energy input over and above this would only be possible by theuse of additional devices provided, for example, by installing otherdispersing implements. Suitable devices would be multistage implementsor the like. In addition, this could only be accomplished by dismantlingthe existing dispersing system.

Thus it is an object of the present invention to provide a dispersingunit, by means of which, in particular, fast introduction of substancesis possible and a change in the energy input can be effectedirrespective of the speed of a rotor.

This object is achieved for a device of the type mentioned above in thatthe stator is mounted for reciprocation in the direction of the rotationaxis of the rotor and can be displaced by a displacement device within aspecified range of movement and can be locked in an arbitrary posit-ion.

Preferred embodiments of the invention are the subject matter of thesub-claims.

In the dispersing unit of the invention, the fact that the stator ismounted for reciprocation in the direction of the rotation axis of therotor and can be displaced by a displacement device within a specifiedrange of movement and may be locked in an arbitrary position means thata dispersing unit is created by means of which an intense pumping actionis produced by axially shifting the stator away from the dispersingzone. This ensures that substances can be introduced either with intenseshearing or very quickly depending on their wetting properties.Furthermore, the input of energy into the product to be treated isinfluenced depending on the state of engagement of the stator in thedispersing zone.

According to a first preferred embodiment of the device of theinvention, provision is made for the displacement device to comprise adisplacement screw provided on the outside wall of the container andhaving a double male thread comprising two parallel individual threadsspaced from each other to form a clearance, whilst a nut covering bothindividual threads can be rotatably displaced along the double malethread, the stator being connected to the nut by a pin passing throughan oblong hole in the wall of the container.

According to another preferred embodiment of the device of theinvention, provision is made for the rotor to have coaxial teeth. Thepumping properties of the device of the invention may be enhanced bysuitably designing the coaxial teeth. Furthermore, pumping impellers canbe mounted on the base of the rotor at the back. In addition, inpreferred embodiments the stator is also provided with coaxial teeth.

According to another preferred embodiment of the device of theinvention, provision is made for the dispersing unit to be equipped withother implements. These may be conical or flat breakers. Furthermore,the coaxially toothed dispersing implements may be multistageimplements.

According to an important preferred embodiment of the device of theinvention, provision is made for the stator to be substantially in theform of a hollow cylinder which is partially open at one end and open atthe other end. In conjunction with a stator thus designed, two rotorsare provided of which one is located in the vicinity of the outerlateral surface of the stator and the other in the vicinity of the innerlateral surface of the stator. One rotor is preferably substantially inthe form of a hollow cylinder having one open end and one closed end,which forms a baseplate, the closed end of said rotor being opposite tothe partially open end of the stator, during operating, and a rotor ispreferably provided with coaxial teeth in the region of its open end.The partially open end of the stator can form an outlet opening for thedispersed product.

In the device of the invention, preferably one or more premix impellersare provided within the container, mounted on a shaft which is in linewith the longitudinal axis of the container.

In order to be able to introduce a large quantity of material into thecontainer, the container, which preferably has the form of a hollowcylinder, is positioned vertical and above it there is provided a binhaving an upper, cylindrical part and a lower, cone-shaped part or apart having the form of a spherical sector, which cone-shaped part orpart having the form of a spherical sector adjoins an upper part of thecontainer or an open end of the container. In order to provide apremixing function, an stirrer is preferably provided in the bin.

In order to achieve multiple treatment of the substances to be dispersedin the container, the device of the invention is preferably providedwith a piping system which leads from a discharge opening for thesubstances to the cone-shaped part of the bin or the part having theform of a spherical sector, this embodiment being preferred when smallerquantities are to be placed in the container. For the same purpose thereis alternatively or additionally provided a piping system which leadsfrom a discharge opening for the substances to the cylindrical part ofthe bin. This embodiment is preferred when larger quantities of materialare to be placed in the container.

According to another important preferred embodiment of the device of theinvention, provision is made for the stator to be in the form of anultrasonic sonotrode (sound emitter). The ultrasonic sonotrode can besubstantially in the form of a hollow cylinder which is partially openat one end and open at the other end and which, when transverseultrasonic vibrations are introduced at the partially open end,automatically assumes at least one vibrational mode in which thedistance of the cylinder wall from the central longitudinal axis of thecylinder periodically changes.

The contrivance of the invention is explained below with reference to apreferred embodiment, which is illustrated in the accompanying drawings,in which

FIG. 1 is a cross-sectional view of a first preferred embodiment of thedevice of the invention;

FIG. 2 is a cross-sectional view of an enlarged portion of the preferredembodiment of the device of the invention illustrated in FIG. 1;

FIG. 3 is a cross-sectional view of an enlarged portion of the preferredembodiment of the device of the invention illustrated in FIG. 2.

FIG. 4 is a cross-sectional view of an enlarged portion of the preferredembodiment of the device of the invention illustrated in FIG. 3.

The device 100 of the invention illustrated in FIGS. 1 to 4 for thedispersion of, in particular, low-viscosity to high-viscosity substanceshas a container 200 with an opening 210 for the introduction of thesubstances to be dispersed and also an opening 220 for the discharge ofthe dispersed substances and contains two rotors 150, 160 and a stator110, which rotors 150, 160 are each mounted for rotation relatively tostator 110 about a rotation axis 155, 165 for the purpose of dispersingsubstances that have been introduced int-o container 200. Stator 110 is,according to an essential feature of the invention, reciprocally mountedin the direction of rotation axis 155 of rotor 150 and can be displacedby means of a displacement device 170 within a specified range ofmovement and can be releasably locked in an arbitrary position. Onaccount of the pumping action produced during the displacement caused bydisplacement device 170, the substances to be introduced can be filledin slowly or quickly with a high degree of precision depending on theirwettability.

Displacement device 170 comprises a double male thread provided on theoutside wall of the container and having two parallel individual threads171, 172 spaced from each other so as to form a clearance, and a nut 173covering both individual threads 171, 172 is rotatably displaceablealong the double male thread, and stator 110 is connected to nut 173 bya pin 220 passing through an oblong hole 210 in the wall of container200.

The two rotors 150, 160 are substantially in the form of hollowcylinders having a closed end forming a baseplate 151, 161 and an openend 152, 162 and provided with coaxial teeth in the region of said openend 152 and the adjoining lateral surface. One of rotors 150 is disposedin the vicinity of the outer lateral surface of stator 110 and the otherrotor 160 is disposed in the vicinity of the inner lateral surface ofstator 110.

Stator 110 is likewise substantially in the form of a hollow cylinderand partially open at one end 111 and open at the other end 112. Stator110 is provided with coaxial teeth in the region of its lateral surface,which teeth are in the form of slits in the lateral surface adapted toallow the passage therethrough of a substance to be dispersed.

Within the container there are provided premix impellers 300, 310, whichare mounted on a shaft 330 in line with the longitudinal axis 230 ofcontainer 200, and above container 200 there is provided a bin 400having an upper, cylindrical part 410 and a lower, cone-shaped part 420,in which bin 400 there is provided an stirrer 430. The cone-shaped part420 of bin 400 is adjacent an upper part 240 of container 200.

A piping system 500 leads from a discharge opening 430 for dispersedsubstances to the cone-shaped part 420 of bin 400, and another pipingsystem 510 leads from a discharge opening 440 for dispersed substancesto the cylindrical part 410 of bin 400.

The depicted dispersing unit of the invention is distinguished in thatstator 110 is in the form of an ultrasonic sonotrode (sound emitter),which is substantially a hollow cylinder which is partially open at oneend and is open at the other end and assumes, when ultrasonic vibrationsare introduced, at least one vibrational mode in which the distance ofthe cylinder wall from the central longitudinal axis of the cylinderperiodically changes.

The embodiment of the invention explained above merely serves thepurpose of providing better clarification of the teaching of: theinvention defined by the claims, which is not, as such, restricted tothis embodiment.

1-17. (canceled)
 18. A device for the dispersion of, in particular, low-viscosity to high-viscosity mixtures of substances, comprising a container having one or more openings for introducing the substances to be dispersed and one or more openings for discharging the dispersed substances, and at least one rotor and one stator, said at least one rotor being mounted for rotation relatively to said stator about an axis of rotation for the purpose of dispersing the substances that have been introduced into the container, wherein said stator is mounted for reciprocation in the direction of said rotation axis of said rotor and is adapted for displacement by means of a displacement device within a specified range of movement and can be locked in an arbitrary position, characterized in that said displacement device comprises a double male thread provided on the outside wall of said container and having two parallel individual threads spaced from each other so as to form a clearance, and a nut covering both individual threads is rotatably displaceable along said double male thread, and said stator is connected to said nut by a pin passing through an oblong hole in the wall of said container.
 19. A device as defined in claim 18, wherein said rotor is substantially in the form of a hollow cylinder which is open at one end and closed at the other end so as to form a baseplate.
 20. A device as defined in claim 19, wherein said rotor is provided with coaxial teeth in the region of said open end.
 21. A device as defined in claim 18, wherein said stator is substantially in the form of a hollow cylinder which is partially open at one end and is open at the other end.
 22. A device as defined in claim 21, wherein said stator is provided with coaxial teeth in the region of said open end.
 23. A device as defined in claim 21, wherein said stator is provide with coaxial teeth in the region of the lateral surface of said hollow cylinder.
 24. A device as defined in claim 18, wherein two rotors are provided, of which one is located in the vicinity of the outer lateral surface of said stator and the other is located in the vicinity of the inner lateral surface of said stator.
 25. A device as defined in claim 18, wherein the dispersing unit formed by said stator and said at least one rotor is additionally provided with conical or flat breakers.
 26. A device as defined in claim 18, wherein said coaxially toothed dispersing implements are in the form of multistage implements.
 27. New A device as defined in claim 18, wherein within said container there are provided one or more premix impellers mounted on a shaft which in line with the longitudinal axis of said container.
 28. New A device as defined in claim 18, wherein above said container there is provided a bin having an upper, cylindrical part and a lower, cone-shaped part, which cone-shaped part is adjacent an upper part of said container.
 29. A device as defined in claim 28, wherein an stirrer is provided in said bin.
 30. A device as defined in claim 28, wherein a piping system is provided which leads from a discharge opening for dispersed substances to said cone-shaped part of said bin.
 31. A device as de-fined in claim 28, wherein a piping system is provided which leads from a discharge opening for dispersed substances to said cylindrical part of said bin.
 32. A device as defined in claim 18, wherein said stator is an ultrasonic sonotrode (sound emitter).
 33. A device as defined in claim 32, wherein said ultrasonic sonotrode (sound emitter) is substantially in the form of a hollow cylinder which is partially open at one end and is open at the other end and assumes, when ultrasonic vibrations are introduced, at least one vibrational mode in which the distance of the cylinder wall from the central longitudinal axis of said cylinder periodically changes. 